The invention relates to the field of computerized object recognition.
Lighting conditions greatly affect the color balance of digital photographs, and can at times produce inconsistent or distorting color casts. Some color balancing techniques, such the Von Kries method and white balancing techniques, operate directly on the red, blue, and green (RGB) channel pixel values of a digital image, to remove the distorting color cast. White balancing typically uses a neutral grey or white reference within the captured image, or an external reference to determine the correction necessary to remove an unrealistic color cast in the image. Other color balancing techniques use a calibration color chart, such as the Macbeth color chart, to determine the adjustment required to remove a color cast.
In addition to the esthetic loss of color-distorted images, an overly warm or cool color cast can impede applications such as automated object recognition. Although most digital cameras have some built-in color-corrective techniques, these are not always adequate to provide the color correction necessary to reliably recognize objects in a highly color-distorted image.
The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the figures.